Need Advice Im ready to start building my Big Bore

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  • Ga426owner

Posted March 14, 2006 - 02:38 PM


Hey I thought that I would share this build out I am doing on my own 03 450. I am turning it into a 480 or 490. Why some of you may ask...good question...I luv this bike. I have raced it, play rode on it and had many items upgraded as many of you already know. I can flat out ride the you know what out of it...It turns, it handles, it has fantastic suspension..and great get up and go...It just needs more! I want to turn it into a Mega Beast of a bike! Also to compete with my friend who just did a 04 CRF450/480. I will still occasionally race it in outlaw races...and just plain roost the crap out of everything else play riding. I just bought a brand new cylinder that I am sending off to be sized for the big bore/nikosil etc........finally from Langcourt. Waiting to get info on tolerances from both sizes - I know the 480 will be more material - less worry for problems...waiting to get more advice on this. Unfortunately a 4 week turn around.... :thumbsup: So I have time to plan on rebuilding any and all necessary worn or wrong potential issues...

Questions that I have are:

1.Should I also replace my valves and valve seat/guides etc...I am still on stock valves etc...- and I would say at least 150-200 hrs or more on the bike. All are still in spec from my last readjust a couple of months ago. Are Kibblewhite SS that much better in a Yami? SS or titanium?
2. My Cam has been tweeked by Crower - (not the exhaust cam) works great stock...should I replace both with Hot Cams or leave as is?
3. I have a complete hinson/GYTR clutch except the clutch cover. Is there any "real" advantage to the GYTR ot Hinson clutch cover?
4. Cam chain & Tensioner just replaced
5. I will keep the stock cylinder/piston for back up
6. I am not stroking it.

Anything else that I am missing? Yea I more tires... :bonk:

Any advice is appreciated...I can not wait to see how this beast will be after this...I feel sorry for anyone riding behind me now.....I guess it will be in my garage for a long long time...I finally will have the perfect 03...... that cost as much as 2 03's: :thumbsup:

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